Correct Answer: D

Rationale: To estimate the number of 1-4 year old children in a population, you can multiply the total population by the percentage of children in that age group. In this case, using the Philippine population composition as reference, which is about 11.5% for 1-4 year olds, the calculation would be 20,000 x 0.115 = 2,300 children.

Correct Answer: D

Rationale: Assessment of the woman should be done first to determine whether she is having true labor and, if so, what stage of labor she is in.

Correct Answer: B

Rationale: Under 5-year-old children are particularly susceptible to protein-energy malnutrition (PEM) because they have generally been weaned and often rely on others for food. This population may suffer from poor intrafamilial food distribution, contributing to their vulnerability.

Correct Answer: B

Rationale: Retinol 200,000 IU, which is a form of megadose Vitamin A, is contraindicated in pregnancy as it may have teratogenic effects, potentially harming the developing fetus. It is important to avoid high doses of Vitamin A during pregnancy to prevent adverse outcomes.

Correct Answer: C

Rationale: The correct term for the method of population assignment based on the actual physical location of the people is 'de facto.' On the other hand, 'de jure' is the method based on the usual place of residence of the people.